1. Field of the Invention (Technical Field)
Embodiments of the present invention relate to a circuit for providing a rapidly sweeping load, which can be used in numerous applications, particularly for use in testing a photovoltaic cell.
2. Description of Related Art
Testing of PV cells under pulsed conditions requires the voltage of the cell to be swept over a range of greater than the open circuit voltage to a negative bias or vice versa. Although numerous manners and circuits are known for testing photovoltaic cells, particularly in an attempt to maintain consistent quality controls for the manufacturer thereof, known systems cannot meet the high speed timing requirements to sweep the load in less than about three milliseconds. Accordingly, known systems do not have the ability provide a sufficiently rapidly changing test load so that changing load tests can be easily and inexpensively incorporated into large-scale photovoltaic cell manufacturing facilities. There is thus a present need for a method and apparatus which provides an inexpensive and easily implemented rapidly-changing load test for photovoltaic cells. Embodiments of the present invention are able to sweep a load within a time of about 10 milliseconds to about 10 microseconds. This allows for testing of PV cells in much faster time frames than currently available.